A5040071113- Crystallization and Solubility Studies
- Synthetic Organic Chemistry Methods
- Organometallic Complex Synthesis and Catalysis
- X-ray Diffraction in Crystallography
- Advanced Polymer Synthesis and Characterization
- Carbon dioxide utilization in catalysis
- Polymer composites and self-healing
- Metal-Catalyzed Oxygenation Mechanisms
- biodegradable polymer synthesis and properties
- Catalysis and Oxidation Reactions
University of Konstanz
2021-2025
The world’s most abundantly manufactured plastic, polyethylene, consists of inert hydrocarbon chains. introduction reactive polar groups in these chains could help overcome problematic environmental persistence and enhance compatibility with other materials. We show that phosphinophenolate-coordinated nickel complexes can catalyze nonalternating copolymerization ethylene carbon monoxide to incorporate a low density individual in-chain keto polyethylene high molecular weight while retaining...
Polyethylene materials with in-chain-incorporated keto groups were recently enabled by nonalternating copolymerization of ethylene carbon monoxide in the presence Ni(II) phosphinephenolate catalysts. We elucidate mechanism this long-sought-for reaction a combined theoretical DFT study catalytically active species and experimental polymer microstructures formed pressure-reactor copolymerizations different The pathway leading to desired incorporation proceeds via cis/trans isomerization an...
Vitrimers can combine the advantageous properties of cross-linked materials with thermoplastic processability. For prominent case polyethylene, established post-polymerization introduction cross-linkable moieties results in extremely heterogeneous compositions chains. Here, we report generation functionalized polyethylenes directly by catalytic insertion polymerization, incorporated aryl boronic esters or alternatively acetal-protected groups suited for cross-linking difunctional esters. In...
Recent breakthroughs in the generation of polar-functionalized and more sustainable degradable polyethylenes have been enabled by advanced phosphinephenolato Ni(II) catalysts. A key has to overcome this type catalysts' propensity for extensive chain transfer enable formation high-molecular-weight polyethylene chains. We elucidate mechanistic origin paradigm shift a combined experimental theoretical study. Single-crystal X-ray structural analysis cyclic voltammetry set six different catalysts...
Endowing polyethylenes with photodegradability via incorporation of low densities in-chain keto units could reduce the problematic environmental persistency littered polymer waste. A breakthrough enabling such materials is recent finding nickel catalyzed nonalternating copolymerization ethylene-carbon monoxide. We reveal irreversible catalyst deactivation pathways operative in this reaction. Reductive elimination common phosphinephenolate Ni(II) motif occurs acyl intermediates formed upon...
The world’s most important plastic, polyethylene, consists of inert hydrocarbon chains. An introduction reactive polar groups in these chains is much sought-after, to overcome the problematic environmental persistency and enhance compatibility with other materials. However, state art catalytic polymerization processes this has not been possible. Here, we show how a low density individual in-chain keto can be generated high molecular weight polyethylene by copolymerization carbon monoxide....
The world’s most important plastic, polyethylene, consists of inert hydrocarbon chains. An introduction reactive polar groups in these chains is much sought-after, to overcome the problematic environmental persistency and enhance compatibility with other materials. However, state art catalytic polymerization processes this has not been possible. Here, we show how a low density individual in-chain keto can be generated high molecular weight polyethylene by copolymerization carbon monoxide....